Инд. авторы:	Borodina U.O, Goryainov S.V., Oreshonkov A., Shatskiy A.F., Rashchenko S.V.
Заглавие:	Raman study of 3.65 angstrom-phase MgSi(OH)(6) under high pressure and the bands assignment
Библ. ссылка:	Borodina U.O, Goryainov S.V., Oreshonkov A., Shatskiy A.F., Rashchenko S.V. Raman study of 3.65 angstrom-phase MgSi(OH)(6) under high pressure and the bands assignment // High Pressure Research. - 2020. - Vol.40. - Iss. 4. - P.495-510. - ISSN 0895-7959. - EISSN 1477-2299.
Внешние системы:	DOI: 10.1080/08957959.2020.1830078; WoS: 000578681000001;
Реферат:	eng: 3.65 angstrom-phase (or hydroxide-perovskite), MgSi(OH)(6), is a representative of dense hydrous magnesium silicates (DHMS) with maximum water content (up to similar to 35 wt.% H2O) and thus is of interest as one of the largest repositories of water among all the known hydrous phases. Sample of 3.65 angstrom-phase, grown in DIA-type multianvil apparatus, was studied by Raman spectroscopy under pressure up to similar to 7 GPa with diamond anvil cell. Interpretation of the Raman spectrum was carried out using lattice-dynamical simulations within ab initio DFT method (CASTEP code). Additionally, OH-stretching bands are analyzed with two phenomenological models: empirical model by Novak and Libowitzky, using correlation between O-O distance and the wavenumber of the OH-stretching band, and theoretical model, using double Morse potentials of hydrogen bond O-H center dot center dot center dot O. Upon the pressure increase, octahedral and bending delta(OH) vibrations exhibit linear positive pressure shift, whereas wavenumbers of the OH-stretching modes show inverse pressure dependence.
Ключевые слова:	THAUMASITE; BEHAVIOR; WATER; SYSTEM; STABILITY; CRYSTAL-CHEMISTRY; MGSIO3 PEROVSKITE; VIBRATIONAL-SPECTRA; HYDROUS MAGNESIUM SILICATES; six-coordinated silicon; high pressure; Raman spectra; dense hydrous magnesium silicates; 3.65 angstrom-phase; DENSE;
Издано:	2020
Физ. характеристика:	с.495-510